1. FIELD OF THE INVENTION
The present invention relates generally to a scroll compressor and, more particularly, to a frame structure which can be easily assembled by improving the manner of attaching a balancer to the frame structure.
2. DESCRIPTION OF THE PRIOR ART
In a conventional low-pressure chamber type of scroll compressor, as described in U.S. Pat. No. 4,065,279, a balancer attached to the drive-shaft side is disposed between a first frame having a bearing portion for rotatably supporting the shaft provided at the back of the base plate of an orbiting scroll and a second frame constituted by a main bearing for rotatably supporting a lower drive shaft and a leg portion to which a motor is fixed, the first and second frames being formed separately from each other. In such a structure, although the assembly of the balancer is easy, two such separate frames are needed, and thus no account is taken of the fact that it is necessary to coaxially assemble the bearing for rotatably supporting the first frame and the main bearing for rotatably supporting the lower drive shaft provided in the second frame.
The aforesaid prior art adopts a structure in which two main bearings are respectively provided in the separately-formed frames in order to give a preference to the manner of attachment of the balancer, but takes no consideration into the aforementioned coaxial assembly of the first and second main bearings. Therefore, when it is necessary to minimize eccentricity which might take place during assembly, a severe working accuracy is required, and this makes the working process difficult and complicated. Accordingly, since the two drive-shaft bearing portions may be assembled in an eccentric state, the drive-shaft bearings would partially strike other adjacent components, thereby causing various problems concerning reliability, for example, the bearings being burnt or damaged.